Complementary metal oxide (CMOS) technology is used to fabricate integrated circuits such as microprocessors, microcontrollers, static random access memory (RAM), digital logic circuits and other circuits. As CMOS devices continue scaling to smaller dimensions, various designs and techniques are employed to improve device performance. CMOS devices include vertical transistors that have source/drain regions that are disposed at opposing ends of a vertical channel region. Vertical transistors are attractive candidates for scaling to smaller dimensions.